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Using USB "stick" adapter inside a cantenna

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Anonymous
July 8, 2004 6:13:31 PM

Archived from groups: alt.internet.wireless (More info?)

Anyone else doing this? Using a USB "stick" type adapter, the one
piece USB adapter with a USB connection on one end? I am using the
D-link DWL-122.
http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
extension cable. I paid $31 for it. So connecting in a cantenna was
simply a matter of drilling a hole then using pliers to enlarge it
enough for the USB connector to go through it. I used a 1-lb coffee
can. The USB type A female connector seems to help keep it snug and
upright in the can. I then strung the USB extension cable out the
window and taped it to the back of a plastic porch chair. Adjusting
the chair and tape to get it angled correctly. I may need to do
something more permanent. Suggestions?

What I liked about it was no soldering or connectors to buy.

I now get a signal strength of 2 out of 5 bars. About what I got
before. But now the connection is reliable. And I am consistently
getting 1.2-1.3 Mbps downloads!

Network Stumbler quotes signal to noise difference of -10dBm.

Anyone else done anything similar?

If anyone else tries to do this, look carefully at the "stick" type
USB adapters. Some do not come with a USB extension cable. I guess
they are oriented for use on laptops. The USB extension cable can
cost $20 or more!

How can I measure the effectiveness of the setup other than what I
have already done?

You can contact me directly at:

bobalston9 AT aol D O T c o m
Anonymous
July 9, 2004 1:46:15 AM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston9@aol.com> wrote:
> http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
> extension cable. I paid $31 for it. So connecting in a cantenna was
> simply a matter of drilling a hole then using pliers to enlarge it
> enough for the USB connector to go through it. I used a 1-lb coffee

Tell me more. I have a DWL-122. I have a coffee can.
Did you drill in the bottom, or the side of the can? Where exactly? How
did you decide where to put the mini-USB? How is it oriented inside the
can? Have you tried different positioning and orientation within the can?

Can you put up a photo?

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 9, 2004 1:46:16 AM

Archived from groups: alt.internet.wireless (More info?)

On Thu, 8 Jul 2004 21:46:15 +0000 (UTC), dold@UsingXUSBX.usenet.us.com
wrote:

> Bob Alston <bobalston9@aol.com> wrote:
>> http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
>> extension cable. I paid $31 for it. So connecting in a cantenna was
>> simply a matter of drilling a hole then using pliers to enlarge it
>> enough for the USB connector to go through it. I used a 1-lb coffee
>
> Tell me more. I have a DWL-122. I have a coffee can.
> Did you drill in the bottom, or the side of the can? Where exactly? How
> did you decide where to put the mini-USB? How is it oriented inside the
> can? Have you tried different positioning and orientation within the can?
>
> Can you put up a photo?
>

<aol> me too! </aol>

If Bob wants to play, he might want to cut a slit in the wall of the can
instead of a hole, so he can slide the stick forward and backward to
determine the best position with respect to the back of the can.

I still like the idea of putting the stick in the back of a car headlight
assembly. <g>

--
Barry
Related resources
Anonymous
July 9, 2004 1:46:16 AM

Archived from groups: alt.internet.wireless (More info?)

dold@UsingXUSBX.usenet.us.com wrote in message news:<cckfb7$g7$1@blue.rahul.net>...
> Bob Alston <bobalston9@aol.com> wrote:
> > http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
> > extension cable. I paid $31 for it. So connecting in a cantenna was
> > simply a matter of drilling a hole then using pliers to enlarge it
> > enough for the USB connector to go through it. I used a 1-lb coffee
>
> Tell me more. I have a DWL-122. I have a coffee can.
> Did you drill in the bottom, or the side of the can? Where exactly? How
> did you decide where to put the mini-USB? How is it oriented inside the
> can? Have you tried different positioning and orientation within the can?
>
> Can you put up a photo?
>
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5

A little more info can be found on this posting on my web site:

http://members.cox.net/tulsaalstons/Documents/Compact%2...

The hole is in the side of the can, at a precise distance from the can
bottom. The flat part of the DWL-122 faces the open end of the can.

Have not tried different positioning as I found the initial one
provided excellent results.

Sorry no pictures available right now.

Bob
Bob
Anonymous
July 9, 2004 2:35:53 PM

Archived from groups: alt.internet.wireless (More info?)

> On Thu, 8 Jul 2004 21:46:15 +0000 (UTC), dold@UsingXUSBX.usenet.us.com
> wrote:
>
> > Bob Alston <bobalston9@aol.com> wrote:
> >> http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
> >> extension cable. I paid $31 for it. So connecting in a cantenna was
> >> simply a matter of drilling a hole then using pliers to enlarge it
> >> enough for the USB connector to go through it. I used a 1-lb coffee
> >
> > Tell me more. I have a DWL-122. I have a coffee can.
> > Did you drill in the bottom, or the side of the can? Where exactly?
How
> > did you decide where to put the mini-USB? How is it oriented inside the
> > can? Have you tried different positioning and orientation within the
can?
> >
> > Can you put up a photo?
> >
>
> <aol> me too! </aol>
>
> If Bob wants to play, he might want to cut a slit in the wall of the can
> instead of a hole, so he can slide the stick forward and backward to
> determine the best position with respect to the back of the can.
>
> I still like the idea of putting the stick in the back of a car headlight
> assembly. <g>
>
> --
> Barry

Thanks for the suggestions but I do not feel I really need to play with the
placement of the stick. I positioned it based on calculations I found at
http://www.turnpoint.net/wireless/cantennahowto.html

Also, I would expect that the car headlight assembly costs a bit more than
an empty coffee can. However YMMV and IMO ect. There are clearly LOTS of
innovative ways to build "cantennas".

Bob


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Anonymous
July 9, 2004 7:39:34 PM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston9@aol.com> wrote:

> http://members.cox.net/tulsaalstons/Documents/Compact%2...

http://makeashorterlink.com/?Q105513C8 goes to that same place.

> The hole is in the side of the can, at a precise distance from the can
> bottom. The flat part of the DWL-122 faces the open end of the can.

The precise distance is the same as for a bare probe?

I assume that a view into the open end of the can looks like a
keyhole, or the same as a standard cantenna "probe" but thicker.

Did you try reversing the mini-USB? I'm not sure if the can acts as a
waveguide, funnelling the RF to the antenna, or a reflector, where you want
the face of the mini-USB pointing toward the closed end.

How far is the mini-USB sticking up into the can? I presume that the
ceramic patch antenna is very near the top. I might expect to try to
center that in the can, although a normal probe is offset all the way to
one side of the can.

> Have not tried different positioning as I found the initial one
> provided excellent results.

Don't mess with success?

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 9, 2004 7:39:35 PM

Archived from groups: alt.internet.wireless (More info?)

> The precise distance is the same as for a bare probe?
>

I believe it is not much different, perhaps by the width of one edge of
the antenna covering, which, when the flat surface is facing the open end of
the can, is not much. Also since the stick is centered in the hole at the
"precise" location, I can ass-ume that the antenna inside the stick is also.
:) 

> I assume that a view into the open end of the can looks like a
> keyhole, or the same as a standard cantenna "probe" but thicker.

Yup
>
> Did you try reversing the mini-USB? I'm not sure if the can acts as a
> waveguide, funnelling the RF to the antenna, or a reflector, where you
want
> the face of the mini-USB pointing toward the closed end.

No. As I understand it, the can acts as a waveguide.

>
> How far is the mini-USB sticking up into the can? I presume that the
> ceramic patch antenna is very near the top. I might expect to try to
> center that in the can, although a normal probe is offset all the way to
> one side of the can.

The mini-USB stick (or dongle) sticks up fully into the can. I pulled
the USB connector down thru the can hold until it stopped at the beginning
of the antenna cover.

>
> > Have not tried different positioning as I found the initial one
> > provided excellent results.
>
> Don't mess with success?

Yup.

But would like to find out more how to measure the results. I have
Network Stumbler and see about -10 dB difference between noise and signal.
Also Win XP reports 2 out of 5 bars. Need to be able to monitor packet
loss/resends.
Speed tests consistently show 1.2 Mbps. Which is slightly less than 1.3
Mbps I get from a PC located close to the antenna.

>
> --
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>


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Anonymous
July 10, 2004 4:23:21 AM

Archived from groups: alt.internet.wireless (More info?)

On Fri, 9 Jul 2004 15:39:34 +0000 (UTC), dold@UsingXUSBX.usenet.us.com
wrote:

>Did you try reversing the mini-USB? I'm not sure if the can acts as a
>waveguide, funnelling the RF to the antenna, or a reflector, where you want
>the face of the mini-USB pointing toward the closed end.

It acts a both a waveguide and a reflector. The USB antenna is
approximately 1/4 wavelength from the bottom of the can.

>How far is the mini-USB sticking up into the can? I presume that the
>ceramic patch antenna is very near the top. I might expect to try to
>center that in the can, although a normal probe is offset all the way to
>one side of the can.

Well, I lied. It's not a ceramic patch antenna like in the older
Linksys WUSB11 radios. It's a chunk of high permittivity/permeability
(polysulfone??) circuit board with an etched gold plated antenna.
See:
http://www.LearnByDestroying.com/pics/wireless/DWL-122/...
The antenna is on the top of the USB dongle (the side with the
flashing lights) and at the very end of the board. That means the
bulk of the RF comes out upward from the device. Looks like it was
made in house as it has no manufacturers stamp on the antenna.

It looks like it would be very easy to unsolder this antenna and
attach a pigtail. Just don't tell the FCC that I suggested this.

The FCC ID is KA22002090025-1
Internal Photos:
https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve...
Test report:
https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve...
From the bottom of the test report:
"4.7.2 ANTENNA CONNECTED CONSTRUCTION
The antenna used in this product is Printed-F Antenna without antenna
connector. And the maximum Gain of this antenna is only –4.56dBi."

Also, If you want (and if I cand find the time), I'll fire up 4NEC2
and conjur an antenna model of the MJB coffee can.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
Anonymous
July 10, 2004 4:23:22 AM

Archived from groups: alt.internet.wireless (More info?)

I wonder then if I constructed my tin cantenna incorrectly. I wrongly
asssssuummed that the antenna was the length of the dongel. Since it is on
the top, perhaps I should lay down the dongle with the top located 1/4
wavelength from the end of the can.

What do you think?



--
Bob Alston

"Jeff Liebermann" <jeffl@comix.santa-cruz.ca.us> wrote in message
news:p naue0h8o6nimbevlhf87meqns9ikkce0b@4ax.com...
> On Fri, 9 Jul 2004 15:39:34 +0000 (UTC), dold@UsingXUSBX.usenet.us.com
> wrote:
>
> >Did you try reversing the mini-USB? I'm not sure if the can acts as a
> >waveguide, funnelling the RF to the antenna, or a reflector, where you
want
> >the face of the mini-USB pointing toward the closed end.
>
> It acts a both a waveguide and a reflector. The USB antenna is
> approximately 1/4 wavelength from the bottom of the can.
>
> >How far is the mini-USB sticking up into the can? I presume that the
> >ceramic patch antenna is very near the top. I might expect to try to
> >center that in the can, although a normal probe is offset all the way to
> >one side of the can.
>
> Well, I lied. It's not a ceramic patch antenna like in the older
> Linksys WUSB11 radios. It's a chunk of high permittivity/permeability
> (polysulfone??) circuit board with an etched gold plated antenna.
> See:
> http://www.LearnByDestroying.com/pics/wireless/DWL-122/...
> The antenna is on the top of the USB dongle (the side with the
> flashing lights) and at the very end of the board. That means the
> bulk of the RF comes out upward from the device. Looks like it was
> made in house as it has no manufacturers stamp on the antenna.
>
> It looks like it would be very easy to unsolder this antenna and
> attach a pigtail. Just don't tell the FCC that I suggested this.
>
> The FCC ID is KA22002090025-1
> Internal Photos:
>
https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve...
> Test report:
>
https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve...
> From the bottom of the test report:
> "4.7.2 ANTENNA CONNECTED CONSTRUCTION
> The antenna used in this product is Printed-F Antenna without antenna
> connector. And the maximum Gain of this antenna is only -4.56dBi."
>
> Also, If you want (and if I cand find the time), I'll fire up 4NEC2
> and conjur an antenna model of the MJB coffee can.
>
>
> --
> # Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
> # 831.336.2558 voice http://www.LearnByDestroying.com
> # jeffl@comix.santa-cruz.ca.us
> # 831.421.6491 digital_pager jeffl@cruzio.com AE6KS

I wonder then if I constructed my tin cantenna incorrectly. I wrongly
asssssuummed that the antenna was the length of the dongel. Since it is on
the top, perhaps I should lay down the dongle with the top located 1/4
wavelength from the end of the can.

What do you think?



--
Bob Alston



---
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Anonymous
July 10, 2004 9:05:06 AM

Archived from groups: alt.internet.wireless (More info?)

On Fri, 9 Jul 2004 21:22:23 -0500, "Bob Alston" <bobalston AT aol
DOT com> wrote:

>I wonder then if I constructed my tin cantenna incorrectly. I wrongly
>asssssuummed that the antenna was the length of the dongel.

Assumption is the mother of all screwups.

>Since it is on
>the top, perhaps I should lay down the dongle with the top located 1/4
>wavelength from the end of the can.

Yep. That's the way it should be done.

>What do you think?

I think I need a vacation. I just trashed 3 hours tinkering with
4NEC2 antenna modeling software trying to model the coffee can. Let's
just say I have a bit more reading to do. Every time I try to
optimize the design, the coffee can just evaporates leaving only the
feed wire. This is not that way it's suppose to work.

So, I decided that someone must have done an NEC2 model of the can by
now. Googlexcavating, I found:
http://www.nec2.org/wlan.htm (near the bottom of page)
which had a ready to run, nec2 deck for a 100mm dia, 300mm long coffee
can feed. A bit of cut-n-paste resulted in the following pictures:
http://www.LearnByDestroying.com/pics/antennas/coffee24...
Note that the feed wire is NOT a simple piece of wire, but a conical
assembly that offers a better match and better bandwidth.

I'm not sure where the optimum location for the USB dongle should be
in the can. My guess(tm) is that dead center, with the flat top of
the dongle (LED lights) facing forward.

However, that's not the way I would do it. The little antenna in the
dongle is inefficient (-4dBi gain) as compared to a simple dipole (or
monopole). I would be tempted to unsolder the antenna, and solder a
1/4wave monopole (or conical feed) to the former "tap" pad on the
board. The metal shield on the back of the board goes flat onto the
can and the monopole (or conical feed) goes through a hole in the side
of the can.

Another way is to build a patch, panel, or biquad antenna assembly
without the coax connector and just attach the USB radio to the back
of the panel, possibly with a very short piece of semi-rigid coax
cable.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
Anonymous
July 10, 2004 9:17:13 AM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 05:05:06 GMT, Jeff Liebermann
<jeffl@comix.santa-cruz.ca.us> wrote:

>So, I decided that someone must have done an NEC2 model of the can by
>now. Googlexcavating, I found:
> http://www.nec2.org/wlan.htm (near the bottom of page)
>which had a ready to run, nec2 deck for a 100mm dia, 300mm long coffee
>can feed. A bit of cut-n-paste resulted in the following pictures:
> http://www.LearnByDestroying.com/pics/antennas/coffee24...

Oops. The can is 100mm dia and 135mm long.
I need a new proof reader.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
Anonymous
July 10, 2004 9:40:11 AM

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> Well, I lied. It's not a ceramic patch antenna like in the older
> Linksys WUSB11 radios. It's a chunk of high permittivity/permeability
> (polysulfone??) circuit board with an etched gold plated antenna.
> See:
> http://www.LearnByDestroying.com/pics/wireless/DWL-122/...

Did you run down and buy one at Fry's for $19.95?

> The antenna is on the top of the USB dongle (the side with the
> flashing lights) and at the very end of the board.

It looks from the photos like it is opposite the LEDs. I think the
dongle-in-a-can shoudl be rotated so the LEDs are facing the closed end.

> That means the bulk of the RF comes out upward from the device.

I tested for off-the-end signal strength. I don't think I found that to be
a strong point, but I need to revisit my testing. I know that the edges
(sides) are not strong, and it seemed like there wasn't much difference
front to back.


> It looks like it would be very easy to unsolder this antenna and
> attach a pigtail.

It's hard to say from these photos, and the fact that this "F" is
perpendicular to the PCB, but the Printed-F uses a very thin feed trace as
part of the antenna. I suppose you could hang a length of wire onto the
end of the board, but it might be difficult to calculate the proper length,
given that a part of the antenna remains on the PCB.

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 10:09:51 AM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 05:40:11 +0000 (UTC),
dold@UsingXUSBX.usenet.us.com wrote:

>Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:

>Did you run down and buy one at Fry's for $19.95?

Nope. $30 at Office Max (no rebate) minus a $10 store discount
coupon. I don't do Fry's unless I'm desperate.

>> The antenna is on the top of the USB dongle (the side with the
>> flashing lights) and at the very end of the board.

>It looks from the photos like it is opposite the LEDs.

Nope. The LED's and the antenna are on the opposite side of the board
as all the exposed electronics in the photo.

>I think the
>dongle-in-a-can shoudl be rotated so the LEDs are facing the closed end.

I beg to differ. The antenna and the LED's should face forward
(toward the mouth of the can).

>I tested for off-the-end signal strength. I don't think I found that to be
>a strong point, but I need to revisit my testing. I know that the edges
>(sides) are not strong, and it seemed like there wasn't much difference
>front to back.

An antenna that small acts like an isotropic (point source) radiator.
The pattern will be fairly hemispherical in all directions. Perhaps
there will be a 1-3dB gain difference between the front and back. Not
much but when every dB counts, it's worth doing it right.

>It's hard to say from these photos, and the fact that this "F" is
>perpendicular to the PCB, but the Printed-F uses a very thin feed trace as
>part of the antenna.

Naw, the antenna should come off easily. I'm used to soldering very
small traces. Magnifying glass, 3 diopter glasses, and a steady hand
are a big help.

>I suppose you could hang a length of wire onto the
>end of the board, but it might be difficult to calculate the proper length,
>given that a part of the antenna remains on the PCB.

Yep. However, methinks you can count on the trace and the opposing
ground being some kind of transmission line. My temptation would be
to attach a dipole (2 wires). The two wires go into the two holes in
the circuit board vacated by the antenna. I gotta calculate the
length to width ratio to get the exact dipole size. It will be
approximately 3.1cm per 1/4 wave section. The gain will be a
theoretical +2.1dBi, which will be approximately +7dB of gain over the
yucky -5dBi internal antenna.

Another temptation is to try a folded dipole instead of a simple
dipole. I suspect that the feed impedance from the radio is a bit
higher than 50 ohms which will make the 200 ohm feed impedance of the
folded dipole more useable. If I'm gonna be juggling antennas, then
I'll probably attach an MMCX SMB or SMC connector so I can easily swap
antennas. Yet another project.

Incidentally, if you wanna take your DWL-122 apart, the locking tabs
are on either side of the USB connector. Push in with a small
screwdriver and it will release. When the USB connector end parts, do
NOT try to seperate the other end as it's really locked in tight.
There should be enough space to remove the board with just the USB end
open.



--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
Anonymous
July 10, 2004 10:21:35 AM

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> On Fri, 9 Jul 2004 21:22:23 -0500, "Bob Alston" <bobalston AT aol
> DOT com> wrote:

>>Since it is on the top, perhaps I should lay down the dongle with the top
>>located 1/4 wavelength from the end of the can.

> Yep. That's the way it should be done.

....

> I'm not sure where the optimum location for the USB dongle should be
> in the can. My guess(tm) is that dead center, with the flat top of
> the dongle (LED lights) facing forward.

It might be that Bob and Jeff are describing "top" differntly.
I think Bob is describing "top" as the end of the stick, with "bottom"
being the USB connector.
http://members.cruzio.com/~jeffl/pics/wireless/DWL-122/...
would be looking down at the top, if I understand Bob correctly.

Jeff seems to be calling the "top" the flat face of the dongle that has the
LEDs on it. If that's the case, I would expect the optimum to be with the
F-antenna centered in the can, roughly where Bob had it already.

(Oops. Closer look at the FCC photos shows that the LEDs aren't in the
center of the board. They are off to the side of the metal pan.
I saw that incorrectly last time I spoke.)

> However, that's not the way I would do it. The little antenna in the
> dongle is inefficient (-4dBi gain) as compared to a simple dipole (or
> monopole). I would be tempted to unsolder the antenna, and solder a
> 1/4wave monopole (or conical feed) to the former "tap" pad on the
> board. The metal shield on the back of the board goes flat onto the
> can and the monopole (or conical feed) goes through a hole in the side
> of the can.

A monopole from the middle leg of the "F", with nothing connected to the
other pads? Solder the PCB shield box to the can?

> Another way is to build a patch, panel, or biquad antenna assembly
> without the coax connector and just attach the USB radio to the back
> of the panel, possibly with a very short piece of semi-rigid coax
> cable.

That could be very tidy. The whole thing could be in a Tupperware
sandwich box. http://www.geocities.com/lincomatic/wifipatchantenna.ht...

Or a toothpick monopole without the can, for omni use.
http://www.geocities.com/lincomatic/homebrewant.html

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 10:21:36 AM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 06:21:35 +0000 (UTC),
dold@UsingXUSBX.usenet.us.com wrote:

>A monopole from the middle leg of the "F", with nothing connected to the
>other pads?

Yep. That's the 'hot' RF trace.

>Solder the PCB shield box to the can?

Nope. There's enough cazapitance between the big metal shield and the
can to make an effective connection at 2.4Ghz. Just tape the board to
the can so it doesn't rattle.

>> Another way is to build a patch, panel, or biquad antenna assembly
>> without the coax connector and just attach the USB radio to the back
>> of the panel, possibly with a very short piece of semi-rigid coax
>> cable.

>That could be very tidy. The whole thing could be in a Tupperware
>sandwich box. http://www.geocities.com/lincomatic/wifipatchantenna.ht...

Yeah, I was thinking more like a PVC or fiberglass NEMA box. Try this
design for a patch antenna:
http://www.qsl.net/k3tz/k3tz.html
http://www.qsl.net/k3tz/images/k3tz.pdf

>Or a toothpick monopole without the can, for omni use.
>http://www.geocities.com/lincomatic/homebrewant.html

Nope. The author made it out of a mild steel coat hanger which would
qualify as one of the worst materials for RF conductivity possible.
Use a piece of stainless, silver plated copper, or silver plated brass
instead. Note that the disassembled Mobile Mark antenna appears to be
made from silver plated something.

Also, the authors revised implimentation of Trevor Marshall's biquad
is still wrong. The coax cable must extend from the ground plane to
the "t" junction. The N connector is a very bad idea for this type of
antenna. It should look like this:
http://trevormarshall.com/bq-soldering.jpg
without the N connector. Well, a flush PCB mount N connector might
work but would still require coax cable or tubeing between the ground
plane and the "t" junction.







--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
July 10, 2004 10:23:26 AM

Archived from groups: alt.internet.wireless (More info?)

> Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>> The antenna is on the top of the USB dongle (the side with the
>> flashing lights) and at the very end of the board.

dold@usingxusbx.usenet.us.com wrote:
> It looks from the photos like it is opposite the LEDs. I think the
> dongle-in-a-can shoudl be rotated so the LEDs are facing the closed end.

Oops. Closer look at the FCC photos shows that the LEDs aren't in the
center of the board. They are off to the side of the metal pan.
I saw that incorrectly last time I spoke.

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5


--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 10:43:53 AM

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>>I think the
>>dongle-in-a-can shoudl be rotated so the LEDs are facing the closed end.

> I beg to differ. The antenna and the LED's should face forward
> (toward the mouth of the can).

I was wrong about the side that had the antenna. I didn't see the light
tubes in the plastic housing, and thought the LEDs weren't on the side with
the shield, since they weren't in the center.

> Naw, the antenna should come off easily. I'm used to soldering very
> small traces. Magnifying glass, 3 diopter glasses, and a steady hand
> are a big help.

I wasn't reffering to the difficulty of removing it, I meant that the trace
that stays on the board is part of the radiator. But maybe that's not true
on the DWL-122, the way it is on the "printed-F" theory pages.

> to attach a dipole (2 wires). The two wires go into the two holes in
> the circuit board vacated by the antenna. I gotta calculate the

Go Jeff, Go!

> I'll probably attach an MMCX SMB or SMC connector so I can easily swap
> antennas. Yet another project.

No. You can't play with a USB dongle, and then pollute it by putting an
antenna on a cable!!!! ;-)

> Incidentally, if you wanna take your DWL-122 apart, the locking tabs
> are on either side of the USB connector.

I gave mine away. I might go visit it on Thursday, when we pop open the
new batch of homebrew. Or I might just buy another one.

> Nope. $30 at Office Max (no rebate) minus a $10 store discount
> coupon. I don't do Fry's unless I'm desperate.

OfficeMax is the place that I avoid only slightly more than CompUSA.
Fry's is within walking distance (not that I do), which makes it more
attractive. Ah, OfficeMax is less than 3 miles away. That's $19.95?

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 10:48:14 AM

Archived from groups: alt.internet.wireless (More info?)

dold@usingxusbx.usenet.us.com wrote:
> OfficeMax is the place that I avoid only slightly more than CompUSA.
> Fry's is within walking distance (not that I do), which makes it more
> attractive. Ah, OfficeMax is less than 3 miles away. That's $19.95?

Okay... BAck to Fry's. It's only $12.99. It must be discontinued.
http://shop1.outpost.com/product/3922878
And it is pretty hot, 40mW, probably to make up for the pathetic antenna
that might disappear soon ;-)

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 1:22:00 PM

Archived from groups: alt.internet.wireless (More info?)

<dold@UsingXUSBX.usenet.us.com> wrote in message
news:cco20u$f6r$2@blue.rahul.net...
> > Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> >> The antenna is on the top of the USB dongle (the side with the
> >> flashing lights) and at the very end of the board.
>
> dold@usingxusbx.usenet.us.com wrote:
> > It looks from the photos like it is opposite the LEDs. I think the
> > dongle-in-a-can shoudl be rotated so the LEDs are facing the closed end.
>
> Oops. Closer look at the FCC photos shows that the LEDs aren't in the
> center of the board. They are off to the side of the metal pan.
> I saw that incorrectly last time I spoke.
>
> --
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>
>
> --
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>

For you guys enjoying the talk about disassembling and soldering, one
objective I had was to find a cantenna design that could be done by
virtually anyone - including me - without soldering or disassembly of the
device. I think for that purpose it works. Perhaps it is not optimal. but
it did solve my range and quality problem.

As I sit here now, I just did a Verizon speed test, my d/l was 1.280 Mbps.
Darned good given the top speed of an ethernet attached PC is about 1.3Mbps.

It appears that the biggest issue I have had is not signal strength, as I
still get 2 out of 5 bars, but rather interference and signal distortion.
It is my guess that is the major advantage of the can - to reduce
interference. Can anyone confirm that?

--
Bob Alston


---
Outgoing mail is certified Virus Free.
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Anonymous
July 10, 2004 1:22:01 PM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 09:22:00 -0500, "Bob Alston" <bobalston AT aol
DOT com> wrote:

>For you guys enjoying the talk about disassembling and soldering, one
>objective I had was to find a cantenna design that could be done by
>virtually anyone - including me - without soldering or disassembly of the
>device. I think for that purpose it works. Perhaps it is not optimal. but
>it did solve my range and quality problem.

I never stated my objective. I don't reallyl have one. However, as
the tinkering developed, I thought it might be nice to take a $30 USB
radio, add a few dollars in antenna parts, and end up with something
like the YDI USB radio:
http://www.ydi.com/products/usb-ant.php
where the radio is intergrated into the antenna.

No pain, no antenna gain. (Ancient RF designers proverb which
basically demands that antennas be modeled, analyzed, and optimized
before they are built).

>As I sit here now, I just did a Verizon speed test, my d/l was 1.280 Mbps.
>Darned good given the top speed of an ethernet attached PC is about 1.3Mbps.
>
>It appears that the biggest issue I have had is not signal strength, as I
>still get 2 out of 5 bars, but rather interference and signal distortion.
>It is my guess that is the major advantage of the can - to reduce
>interference. Can anyone confirm that?

Antenna gain alway results in a more "directional" antenna. By that,
I mean that antennas do not generate RF. They re-direct it. Signal
that was going in all kinds of useless directions now goes in a
generally more useful direction with a can antenna. The same applies
to reception. You're no longer hearing nearby sources of interference
and have also reduced your reception of reflections off walls and
objects. Gain is good. More gain is better.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
July 10, 2004 8:36:54 PM

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> Also, the authors revised implimentation of Trevor Marshall's biquad
> is still wrong. The coax cable must extend from the ground plane to
> the "t" junction.

I thought about that while looking at http://martybugs.net/wireless/biquad/
definitely a shrouded conductor instead of a radiator coming through the
reflector.

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 9:11:40 PM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:

> For you guys enjoying the talk about disassembling and soldering, one
> objective I had was to find a cantenna design that could be done by
> virtually anyone - including me - without soldering or disassembly of the
> device. I think for that purpose it works. Perhaps it is not optimal. but
> it did solve my range and quality problem.

http://www.LearnByDestroying.com Jeff's site. It's what he does.

I ponder about things. I already had an SMC WiFi card, but I bought an
Orinoco PCCard because it had an external antenna connector, and I thought
that was important. Then I spent $20 on a little chunk of cable that
wasn't long enough for where I needed it. I built antennas that didn't
give much improvement, I traded for an expensive antenna that wasn't any
better than the tin foil reflectors. Jeff didn't like my wrinkly tin foil.
If I made that reflector out of 50 cents of aluminum flashing, it might be
better than the $150 Conifer for my application.
< http://www.rahul.net/dold/clarence/SMC/EZ10-strength.ht... >

I like the mini-USB. A friend already has a card with no connector, just
like I did. I bought a new card with a connector and didn't really gain
much. For less money than a new card, I bought a mini-USB and a five meter
cable. It almost works. (The goal is to hit a local hotspot, so he can
get rid of his landline and dialup account.) Your can would probably work.
The "look ma, no soldering" approach also allows you to use it on the road
with a laptop. The USB cable, dangling from the rear view mirror, would
almost certainly work in the parking lot of a Starbucks, which I prefer to
the noisy interior of the same coffee shop.

I will probably put the unmolested DWL-122 into some can.
I have a Country Time Lemonade can that's tall, so I thought it would be
good. The coffee can really isn't long enough. My lemonade can is 5"
diameter, though, so it's too big, with the TM01 cutoff at 1806MHz, but
others use a single 3lb coffee can, which is way wider and too stubby.
My 5" can is 9" long, well past 3/4 guide wavelength.

> It appears that the biggest issue I have had is not signal strength, as I
> still get 2 out of 5 bars, but rather interference and signal distortion.

When I first put up my reflectors, the biggest difference was not the
signal strength, but the stability and orientation. It used to be that if
I adjusted my sitting position, I would lose my connection. That doesn't
happen anymore.

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 9:11:41 PM

Archived from groups: alt.internet.wireless (More info?)

<dold@UsingXUSBX.usenet.us.com> wrote in message
news:ccp80c$658$1@blue.rahul.net...
> Bob Alston <bobalston AT aol DOT com> wrote:
>
> > For you guys enjoying the talk about disassembling and soldering, one
> > objective I had was to find a cantenna design that could be done by
> > virtually anyone - including me - without soldering or disassembly of
the
> > device. I think for that purpose it works. Perhaps it is not optimal.
but
> > it did solve my range and quality problem.
>
> http://www.LearnByDestroying.com Jeff's site. It's what he does.
>
> I ponder about things. I already had an SMC WiFi card, but I bought an
> Orinoco PCCard because it had an external antenna connector, and I thought
> that was important. Then I spent $20 on a little chunk of cable that
> wasn't long enough for where I needed it. I built antennas that didn't
> give much improvement, I traded for an expensive antenna that wasn't any
> better than the tin foil reflectors. Jeff didn't like my wrinkly tin
foil.
> If I made that reflector out of 50 cents of aluminum flashing, it might be
> better than the $150 Conifer for my application.
> < http://www.rahul.net/dold/clarence/SMC/EZ10-strength.ht... >
>
> I like the mini-USB. A friend already has a card with no connector, just
> like I did. I bought a new card with a connector and didn't really gain
> much. For less money than a new card, I bought a mini-USB and a five
meter
> cable. It almost works. (The goal is to hit a local hotspot, so he can
> get rid of his landline and dialup account.) Your can would probably
work.
> The "look ma, no soldering" approach also allows you to use it on the road
> with a laptop. The USB cable, dangling from the rear view mirror, would
> almost certainly work in the parking lot of a Starbucks, which I prefer to
> the noisy interior of the same coffee shop.
>
> I will probably put the unmolested DWL-122 into some can.
> I have a Country Time Lemonade can that's tall, so I thought it would be
> good. The coffee can really isn't long enough. My lemonade can is 5"
> diameter, though, so it's too big, with the TM01 cutoff at 1806MHz, but
> others use a single 3lb coffee can, which is way wider and too stubby.
> My 5" can is 9" long, well past 3/4 guide wavelength.
>
> > It appears that the biggest issue I have had is not signal strength, as
I
> > still get 2 out of 5 bars, but rather interference and signal
distortion.
>
> When I first put up my reflectors, the biggest difference was not the
> signal strength, but the stability and orientation. It used to be that if
> I adjusted my sitting position, I would lose my connection. That doesn't
> happen anymore.
>
> --
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>
Interesting comments.

I just finished ruining another coffee can, mounting the USB "stick" or
dongle in the end of the can, positing the top of the USB device at approx
1/4 wavelength from the end. Aimed the same. Clearly not nearly as good.
I put it back in the old can and it is working just as well again.

Bob


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
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Anonymous
July 10, 2004 9:11:42 PM

Archived from groups: alt.internet.wireless (More info?)

"Bob Alston" <bobalston AT aol DOT com> wrote in message
news:40f024a7_1@newsfeed.slurp.net...
>
>
>
> <dold@UsingXUSBX.usenet.us.com> wrote in message
> news:ccp80c$658$1@blue.rahul.net...
> > Bob Alston <bobalston AT aol DOT com> wrote:
> >
> > > For you guys enjoying the talk about disassembling and soldering, one
> > > objective I had was to find a cantenna design that could be done by
> > > virtually anyone - including me - without soldering or disassembly of
> the
> > > device. I think for that purpose it works. Perhaps it is not
optimal.
> but
> > > it did solve my range and quality problem.
> >
> > http://www.LearnByDestroying.com Jeff's site. It's what he does.
> >
> > I ponder about things. I already had an SMC WiFi card, but I bought an
> > Orinoco PCCard because it had an external antenna connector, and I
thought
> > that was important. Then I spent $20 on a little chunk of cable that
> > wasn't long enough for where I needed it. I built antennas that didn't
> > give much improvement, I traded for an expensive antenna that wasn't any
> > better than the tin foil reflectors. Jeff didn't like my wrinkly tin
> foil.
> > If I made that reflector out of 50 cents of aluminum flashing, it might
be
> > better than the $150 Conifer for my application.
> > < http://www.rahul.net/dold/clarence/SMC/EZ10-strength.ht... >
> >
> > I like the mini-USB. A friend already has a card with no connector,
just
> > like I did. I bought a new card with a connector and didn't really gain
> > much. For less money than a new card, I bought a mini-USB and a five
> meter
> > cable. It almost works. (The goal is to hit a local hotspot, so he can
> > get rid of his landline and dialup account.) Your can would probably
> work.
> > The "look ma, no soldering" approach also allows you to use it on the
road
> > with a laptop. The USB cable, dangling from the rear view mirror, would
> > almost certainly work in the parking lot of a Starbucks, which I prefer
to
> > the noisy interior of the same coffee shop.
> >
> > I will probably put the unmolested DWL-122 into some can.
> > I have a Country Time Lemonade can that's tall, so I thought it would be
> > good. The coffee can really isn't long enough. My lemonade can is 5"
> > diameter, though, so it's too big, with the TM01 cutoff at 1806MHz, but
> > others use a single 3lb coffee can, which is way wider and too stubby.
> > My 5" can is 9" long, well past 3/4 guide wavelength.
> >
> > > It appears that the biggest issue I have had is not signal strength,
as
> I
> > > still get 2 out of 5 bars, but rather interference and signal
> distortion.
> >
> > When I first put up my reflectors, the biggest difference was not the
> > signal strength, but the stability and orientation. It used to be that
if
> > I adjusted my sitting position, I would lose my connection. That
doesn't
> > happen anymore.
> >
> > --
> > ---
> > Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
> >
> Interesting comments.
>
> I just finished ruining another coffee can, mounting the USB "stick" or
> dongle in the end of the can, positing the top of the USB device at approx
> 1/4 wavelength from the end. Aimed the same. Clearly not nearly as good.
> I put it back in the old can and it is working just as well again.
>
> Bob
>
>
> ---
> Outgoing mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.718 / Virus Database: 474 - Release Date: 7/9/2004
>
>

Tried doubling the length of the coffee can. It actually made signal to
noise ratio a little bit worse.

--
Bob Alston


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
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Anonymous
July 10, 2004 9:25:18 PM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:

> I just finished ruining another coffee can, mounting the USB "stick" or
> dongle in the end of the can, positing the top of the USB device at approx
> 1/4 wavelength from the end. Aimed the same. Clearly not nearly as good.
> I put it back in the old can and it is working just as well again.

That's the difference between your definition of "top", and Jeff's
definition of "top". I would say Jeff is referring to "top side" with the
dongle lying flat on a table, which is how you had it in the first place.

I don't know what a one pound coffee can is, though. What is the diameter
and length of your can? The smaller coffee can seemed to need two cans to
get enough lenght according to the turnpoint calculator.

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 10, 2004 9:25:19 PM

Archived from groups: alt.internet.wireless (More info?)

<dold@UsingXUSBX.usenet.us.com> wrote in message
news:ccp8pu$6k3$1@blue.rahul.net...
> Bob Alston <bobalston AT aol DOT com> wrote:
>
> > I just finished ruining another coffee can, mounting the USB "stick" or
> > dongle in the end of the can, positing the top of the USB device at
approx
> > 1/4 wavelength from the end. Aimed the same. Clearly not nearly as
good.
> > I put it back in the old can and it is working just as well again.
>
> That's the difference between your definition of "top", and Jeff's
> definition of "top". I would say Jeff is referring to "top side" with the
> dongle lying flat on a table, which is how you had it in the first place.
>
> I don't know what a one pound coffee can is, though. What is the diameter
> and length of your can? The smaller coffee can seemed to need two cans to
> get enough lenght according to the turnpoint calculator.
>
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>
My coffee can is 11.x oz of coffee. It is approx 3.75 inches in diameter -
if I recall right. And when I used the calculator, it was a bit too large
but seems to be close enough.

Anyone seen stats on different cantennas where only the diameter of the can
changed? When you get close enough, I wonder if it makes any measurable
difference?

Also, just placed the can on a tripod and raised it up about another foot -
well above the metal railing of the deck. Only so much I can raise it with
the short cable that came with it. That change increased my signal to noise
difference from -10 dBi to -20 dBi. Running a ping test with -t to measure
the reliability of the connection over time.

Anyone know a cheap source of USB extension cables with A-male on one end
and A-female on the other?

Bob Alston



---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.718 / Virus Database: 474 - Release Date: 7/9/2004
Anonymous
July 11, 2004 12:01:57 AM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:
> My coffee can is 11.x oz of coffee. It is approx 3.75 inches in diameter -
> if I recall right. And when I used the calculator, it was a bit too large
> but seems to be close enough.

That would need at least 5.56" length, which is where I thought it came up
short.

> Anyone seen stats on different cantennas where only the diameter of the can
> changed? When you get close enough, I wonder if it makes any measurable
> difference?

http://www.turnpoint.net/wireless/has.html

> Also, just placed the can on a tripod and raised it up about another foot -
> well above the metal railing of the deck. Only so much I can raise it with
> the short cable that came with it. That change increased my signal to noise
> difference from -10 dBi to -20 dBi. Running a ping test with -t to measure
> the reliability of the connection over time.

Wow. That should be helpful.

> Anyone know a cheap source of USB extension cables with A-male on one end
> and A-female on the other?

I bought 5m (the maximum non-amplified) for $9.95 at Fry's.
Office Depot even sells them, but they're more expensive.

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 11, 2004 12:01:58 AM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 20:01:57 +0000 (UTC), dold@UsingXUSBX.usenet.us.com
wrote:

> Bob Alston <bobalston AT aol DOT com> wrote:
>> My coffee can is 11.x oz of coffee. It is approx 3.75 inches in diameter -
>> if I recall right. And when I used the calculator, it was a bit too large
>> but seems to be close enough.
>
> That would need at least 5.56" length, which is where I thought it came up
> short.
>
>> Anyone seen stats on different cantennas where only the diameter of the can
>> changed? When you get close enough, I wonder if it makes any measurable
>> difference?
>
> http://www.turnpoint.net/wireless/has.html
>
>> Also, just placed the can on a tripod and raised it up about another foot -
>> well above the metal railing of the deck. Only so much I can raise it with
>> the short cable that came with it. That change increased my signal to noise
>> difference from -10 dBi to -20 dBi. Running a ping test with -t to measure
>> the reliability of the connection over time.
>
> Wow. That should be helpful.
>
>> Anyone know a cheap source of USB extension cables with A-male on one end
>> and A-female on the other?
>
> I bought 5m (the maximum non-amplified) for $9.95 at Fry's.
> Office Depot even sells them, but they're more expensive.

Here's an active one for that price:

<http://www.pccables.com/cgi-bin/orders6.cgi?action=Show...;

--
Barry
Anonymous
July 11, 2004 3:07:17 AM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 16:36:54 +0000 (UTC),
dold@UsingXUSBX.usenet.us.com wrote:

>Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>> Also, the authors revised implimentation of Trevor Marshall's biquad
>> is still wrong. The coax cable must extend from the ground plane to
>> the "t" junction.

>I thought about that while looking at http://martybugs.net/wireless/biquad/
>definitely a shrouded conductor instead of a radiator coming through the
>reflector.

Yep. That's the right way to do it. Also see:
http://reseaucitoyen.be/?BiQuad
http://sharon.esrac.ele.tue.nl/pub/antenne/13-double-qu...
http://www.xaviervl.com/Antenne/Bi-quad/index.html

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831.336.2558 voice http://www.LearnByDestroying.com
# jeffl@comix.santa-cruz.ca.us
# 831.421.6491 digital_pager jeffl@cruzio.com AE6KS
Anonymous
July 13, 2004 2:45:57 AM

Archived from groups: alt.internet.wireless (More info?)

On Sat, 10 Jul 2004 12:16:19 -0500, "Bob Alston" <bobalston AT aol
DOT com> wrote:

>I just finished ruining another coffee can, mounting the USB "stick" or
>dongle in the end of the can, positing the top of the USB device at approx
>1/4 wavelength from the end. Aimed the same. Clearly not nearly as good.
>I put it back in the old can and it is working just as well again.
>Bob

This might help. I blundered across a web page that has a decent
Excel spreadsheet for calculating cantennas.
http://www.ivor.it/wireless/cantenna.html
One really nice feature of the spreadsheet is that it generates an
NEC2 model file that I can feed to 4NEC2 program to generate models.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
July 13, 2004 1:58:42 PM

Archived from groups: alt.internet.wireless (More info?)

"Jeff Liebermann" <jeffl@comix.santa-cruz.ca.us> wrote in message
news:uet6f0hn3gagnbf27mt0okpqcbtap12prq@4ax.com...
> On Sat, 10 Jul 2004 12:16:19 -0500, "Bob Alston" <bobalston AT aol
> DOT com> wrote:
>
> >I just finished ruining another coffee can, mounting the USB "stick" or
> >dongle in the end of the can, positing the top of the USB device at
approx
> >1/4 wavelength from the end. Aimed the same. Clearly not nearly as
good.
> >I put it back in the old can and it is working just as well again.
> >Bob
>
> This might help. I blundered across a web page that has a decent
> Excel spreadsheet for calculating cantennas.
> http://www.ivor.it/wireless/cantenna.html
> One really nice feature of the spreadsheet is that it generates an
> NEC2 model file that I can feed to 4NEC2 program to generate models.
>
>
> --
> Jeff Liebermann jeffl@comix.santa-cruz.ca.us
> 150 Felker St #D http://www.LearnByDestroying.com
> Santa Cruz CA 95060 AE6KS 831-336-2558

Thanks. but originally I used such a calculator. My original, and best to
date, was placing the dongle through the side of the can, approx. 1/4
wavelength from the bottom.

What I was referring to above was a test, running the dongle throught the
can's bottom. It wasn't nearly as good. At the time I thought the antenna
was across the short end of the dongle. I was wrong. It runs across a
front edge, lengthwise.

Bob


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Anonymous
July 14, 2004 2:25:15 AM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:
> What I was referring to above was a test, running the dongle throught the
> can's bottom. It wasn't nearly as good. At the time I thought the antenna
> was across the short end of the dongle. I was wrong. It runs across a
> front edge, lengthwise.

I fear we will never sort out the orientation of "top", nor where the
antenna is, for the life of this thread. And even after discovering those
two, Jeff used the word "hemispeherical" for the radiation pattern without
giving an orientation of that either.

My pie tin reflector tests with the DWL-122 showed a difference between
horizontal and vertical polarization with the face flat toward the WAP.
Edge on, with the dongle lying flat on a table, was not good. Pointing the
dongle like a mini-keychain-flashlight was not good.


The antenna is just a tiny thing, running along the front side near the top
edge of the PCB. It sits on edge, and I think the radiation is off the
long skinny edge, toward you in the ASCII art below.

------
/ .... \ Antenna across the top front ....
| |
| |
| |
| |
| + | LED
| + | LED
| |
--------
| | USB Connector
----

I plan on some tests Thursday night
I have a WinXP laptop and DWL-122 on a five meter cable
I have a 9" pie plate
I have a Country Time Lemonade cardboard tin
I have a "1 lb" coffee can
I have a "3 lb" coffee can (these vary in size from brand to brand)
I have a win2000 laptop with Orinoco that I will use as a partner for
signal level testing at a range of 20 feet
I have a commercial hotspot of some flavor about 200 yards away
I have a digital camera

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 14, 2004 2:25:16 AM

Archived from groups: alt.internet.wireless (More info?)

Good luck.

Be sure to use the calculations in this link for size of tin can and
placement of antenna:

http://www.turnpoint.net/wireless/cantennahowto.html

--
Bob Alston

<dold@UsingXUSBX.usenet.us.com> wrote in message
news:cd1ngb$520$2@blue.rahul.net...
> Bob Alston <bobalston AT aol DOT com> wrote:
> > What I was referring to above was a test, running the dongle throught
the
> > can's bottom. It wasn't nearly as good. At the time I thought the
antenna
> > was across the short end of the dongle. I was wrong. It runs across a
> > front edge, lengthwise.
>
> I fear we will never sort out the orientation of "top", nor where the
> antenna is, for the life of this thread. And even after discovering those
> two, Jeff used the word "hemispeherical" for the radiation pattern without
> giving an orientation of that either.
>
> My pie tin reflector tests with the DWL-122 showed a difference between
> horizontal and vertical polarization with the face flat toward the WAP.
> Edge on, with the dongle lying flat on a table, was not good. Pointing
the
> dongle like a mini-keychain-flashlight was not good.
>
>
> The antenna is just a tiny thing, running along the front side near the
top
> edge of the PCB. It sits on edge, and I think the radiation is off the
> long skinny edge, toward you in the ASCII art below.
>
> ------
> / .... \ Antenna across the top front ....
> | |
> | |
> | |
> | |
> | + | LED
> | + | LED
> | |
> --------
> | | USB Connector
> ----
>
> I plan on some tests Thursday night
> I have a WinXP laptop and DWL-122 on a five meter cable
> I have a 9" pie plate
> I have a Country Time Lemonade cardboard tin
> I have a "1 lb" coffee can
> I have a "3 lb" coffee can (these vary in size from brand to brand)
> I have a win2000 laptop with Orinoco that I will use as a partner for
> signal level testing at a range of 20 feet
> I have a commercial hotspot of some flavor about 200 yards away
> I have a digital camera
>
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>

Good luck.

Be sure to use the calculations in this link for size of tin can and
placement of antenna:

http://www.turnpoint.net/wireless/cantennahowto.html

I continue to get low signal 38% or 2 of 5 bars, but 11 Mbps transfer rate
and generally constant connectivity. What is interesting is that my signal
to noise difference is 2/3 of the time -20 dB and 1/3 only -10 dB. Not sure
why?

--
Bob Alston


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Anonymous
July 14, 2004 8:07:35 AM

Archived from groups: alt.internet.wireless (More info?)

This has been an enlightening thread...

I am a bit new to wireless networking and just finished doing a
Wireless router with three buildings having AP's with YAGI antennas.
Everyone writes about using a meter to test signal and noise strength.
I am using Planet wireless router and Access Points and no software
like that came with it. Where can I get some software to measure my
signal strength? Also, can anyone tell me how to aim this kind of
YAGI antenna?
http://tinyurl.com/45pwu

Thanks for your help,
Glenn


--
gwoiler
brought to you by http://www.wifi-forum.com/
Anonymous
July 14, 2004 8:07:36 AM

Archived from groups: alt.internet.wireless (More info?)

"gwoiler" <gwoiler.19d8ea@no-mx.forums.yourdomain.com.au> wrote in message
news:gwoiler.19d8ea@no-mx.forums.yourdomain.com.au...
>
> This has been an enlightening thread...
>
> I am a bit new to wireless networking and just finished doing a
> Wireless router with three buildings having AP's with YAGI antennas.
> Everyone writes about using a meter to test signal and noise strength.
> I am using Planet wireless router and Access Points and no software
> like that came with it. Where can I get some software to measure my
> signal strength? Also, can anyone tell me how to aim this kind of
> YAGI antenna?
> http://tinyurl.com/45pwu
>
> Thanks for your help,
> Glenn
>
>
> --
> gwoiler
> brought to you by http://www.wifi-forum.com/
>
I use Network Stumbler to measure signal and noise ratios.

--
Bob Alston



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Anonymous
July 14, 2004 8:07:36 AM

Archived from groups: alt.internet.wireless (More info?)

On Wed, 14 Jul 2004 04:07:35 GMT, gwoiler
<gwoiler.19d8ea@no-mx.forums.yourdomain.com.au> wrote:

>This has been an enlightening thread...

One must suffer before enlightenment.

>I am a bit new to wireless networking and just finished doing a
>Wireless router with three buildings having AP's with YAGI antennas.
>Everyone writes about using a meter to test signal and noise strength.
>I am using Planet wireless router and Access Points and no software
>like that came with it. Where can I get some software to measure my
>signal strength?

http://www.netstumbler.com
Version 0.4 only works with W2K and XP.
Use Ver 0.3.23 for W98 and ME.

All 802.11 access points and client radios send their received signal
strength and S/N (signal to noise) ratio values in unencrypted
managment packets. Even if your access point or client radio does not
have a built in signal strength measuring utility, you can extract the
numbers out of thin air by monitoring (er... sniffing) with
Netstumbler. There is a limited number of supported cards, so check
the shopping list in the FAQ before enlightenment.

For Linux, see Kismet or DStumbler.

>Also, can anyone tell me how to aim this kind of
>YAGI antenna?
>http://tinyurl.com/45pwu

Point and shoot. You have a 30 degree beamwidth. You can't miss. If
the boom is hollow, just sight through it optically. If you have a
rifle scope, just rubber band it to the boom.

I dunno why you decided upon a 13dBi Yagi antenna for $125. You can
get the same gain in a small panel antenna for perhaps half the price.
Yep. $51.
http://www.fab-corp.com
See "Antennas Panel" section.


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
July 14, 2004 8:15:53 AM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:
> Be sure to use the calculations in this link for size of tin can and
> placement of antenna:

> http://www.turnpoint.net/wireless/cantennahowto.html

You said "1/4 wavelength" earlier. I presume you meant Lg, not Lo. Lo is
the same for any can for 802.11b frequencies, Lg would vary with diameter.
I see your 3.75" coffee can as needing the radiator at 1.86". The total
waveguide length should be 7.5" or a minimum of 5.5", which is where the
coffee cans fall short.

I compared the turnpoint figures to the
http://www.ivor.it/wireless/cantenna.html measurements, and they look the
same, although ivor says he found discrepancies with some online
calculator. ivor is a little harder to use. But it adds a TE21 frequency
that you "must" be below. That is only 1949MHz for the 3lb coffee can, and
2339MHz for the Lemonade. Ignoring that, the 3lb coffe can did well in the
turnpoint shootout.

That reminds me that I want to test with channels 1,6,11 for general
antenna comparison, and whatever the target WAP is set to, for this
comparison. Since you control your WAP, you could adjust the channel.

I have my holes/slots drilled. Ready to go. All I need is the dongle. I
found that two 5/16" holes slightly overlapped is enough to feed the USB
connector through and provide support. Can diameter will vary the apparent
placement of the radiator radially inside the can. I can wiggle it back
and forth a bit for tuning... of sorts.

I recall that some test, maybe on turnpoint, pointed out a discrepancy in
measurements for the radiator point for the 3 lb coffee can. I think the
"wrongish" value is measuring up on the outside of the can, adding the 1/4"
for the offset of the floor of the can. They would agree then.

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
July 14, 2004 5:18:08 PM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston wrote:
> <dold@UsingXUSBX.usenet.us.com> wrote in message
> news:ccp8pu$6k3$1@blue.rahul.net...
>
>>Bob Alston <bobalston AT aol DOT com> wrote:
>>
>>
>>>I just finished ruining another coffee can, mounting the USB "stick" or
>>>dongle in the end of the can, positing the top of the USB device at
>>
> approx
>
>>>1/4 wavelength from the end. Aimed the same. Clearly not nearly as
>>
> good.
>
>>>I put it back in the old can and it is working just as well again.
>>
>>That's the difference between your definition of "top", and Jeff's
>>definition of "top". I would say Jeff is referring to "top side" with the
>>dongle lying flat on a table, which is how you had it in the first place.
>>
>>I don't know what a one pound coffee can is, though. What is the diameter
>>and length of your can? The smaller coffee can seemed to need two cans to
>>get enough lenght according to the turnpoint calculator.
>>
>>---
>>Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>>
>
> My coffee can is 11.x oz of coffee. It is approx 3.75 inches in diameter -
> if I recall right. And when I used the calculator, it was a bit too large
> but seems to be close enough.
>
> Anyone seen stats on different cantennas where only the diameter of the can
> changed? When you get close enough, I wonder if it makes any measurable
> difference?
>
> Also, just placed the can on a tripod and raised it up about another foot -
> well above the metal railing of the deck. Only so much I can raise it with
> the short cable that came with it. That change increased my signal to noise
> difference from -10 dBi to -20 dBi. Running a ping test with -t to measure
> the reliability of the connection over time.
>
> Anyone know a cheap source of USB extension cables with A-male on one end
> and A-female on the other?


I bought an A-B female-female adapter at Frys. Lets me use any ole
A-B cable as an extension. Cheaper than a special cable.
mike


--
Return address is VALID.
Bunch of stuff For Sale and Wanted at the link below.
Compaq Aero floppy,ram,battery.
FT-212RH 2-meter 45W transceiver.
Toshiba & Compaq LiIon Batteries, Test Equipment
30pS pulser, Tektronix Concept Books, spot welding head...
http://www.geocities.com/SiliconValley/Monitor/4710/
Anonymous
July 14, 2004 7:55:05 PM

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> http://www.netstumbler.com
> Version 0.4 only works with W2K and XP.
> Use Ver 0.3.23 for W98 and ME.

0.4 appears to work with "any" card, where 0.3 worked with a few.
(Now that I've said that, I'll have to retry my SMC, which I abandoned in
favor of an Orinoco for marginally better quality, but primarily for
NetStumbler and an external antenna jack.)

---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 14, 2004 7:55:06 PM

Archived from groups: alt.internet.wireless (More info?)

On Wed, 14 Jul 2004 15:55:05 +0000 (UTC),
dold@UsingXUSBX.usenet.us.com wrote:

>Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>> http://www.netstumbler.com
>> Version 0.4 only works with W2K and XP.
>> Use Ver 0.3.23 for W98 and ME.

>0.4 appears to work with "any" card, where 0.3 worked with a few.
>(Now that I've said that, I'll have to retry my SMC, which I abandoned in
>favor of an Orinoco for marginally better quality, but primarily for
>NetStumbler and an external antenna jack.)

One thing I know for sure is that Netstumbler 0.4 doesn't work on my
Win98 laptop, while 0.3.23 does. Uninstalling Netstumbler 0.4 also
vaporized some windoze file (forgot the name) that I had to replace.
I repeated the exercise on another WinME laptop with identical
results.

The compatibility list for 0.4 at:
http://www.stumbler.net/compat/
shows some cards that won't work and mentions that
"On Windows XP, most 802.11b, 802.11a, and 802.11g adapters should
work. They may also work on Windows 2000 with recent drivers
installed."

From the 0.4 help file:

"The following are rules of thumb that you can follow in case you
cannot reach the web site for some reason.

This version of NetStumbler requires Windows 2000, Windows XP, or
better.

The Proxim models 8410-WD and 8420-WD are known to work. The 8410-WD
has also been sold as the Dell TrueMobile 1150, Compaq WL110, Avaya
Wireless 802.11b PC Card, and others.

Most cards based on the Intersil Prism/Prism2 chip set also work.

Most 802.11b, 802.11a and 802.11g wireless LAN adapters should work
on Windows XP. Some may work on Windows 2000 too. Many of them
report inaccurate Signal strength, and if using the "NDIS 5.1" card
access method then Noise level will not be reported. This includes
cards based on Atheros, Atmel, Broadcom, Cisco and Centrino chip
sets.

I cannot help you figure out what chip set is in any given card."


--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 AE6KS 831-336-2558
Anonymous
July 15, 2004 1:25:52 AM

Archived from groups: alt.internet.wireless (More info?)

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
> On Wed, 14 Jul 2004 15:55:05 +0000 (UTC),
> dold@UsingXUSBX.usenet.us.com wrote:

>>Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> wrote:
>>> http://www.netstumbler.com
>>> Version 0.4 only works with W2K and XP.
>>> Use Ver 0.3.23 for W98 and ME.

>>0.4 appears to work with "any" card, where 0.3 worked with a few.
>>(Now that I've said that, I'll have to retry my SMC, which I abandoned in
>>favor of an Orinoco for marginally better quality, but primarily for
>>NetStumbler and an external antenna jack.)

> One thing I know for sure is that Netstumbler 0.4 doesn't work on my
> Win98 laptop, while 0.3.23 does.

I neglected to restate that caveat, but, yes, I was only referring to my
Win2000 laptop. Upon further review, it doesn't like my SMC2435W any more
now than it used to. It shows it as unsupported in 0.4, where 0.3 might
have not shown it at all.

The DLink DWL-122 (at the start of this thread) was not seen by 0.3, but
was seen by 0.4 as both a native device and a NDIS device. It does exhibit
very sluggish behavior while NetStumbler is running.

I thought there might be NDIS drivers for the SMC, but I think I'll just
give up on that thought.
Anonymous
July 29, 2004 8:54:12 PM

Archived from groups: alt.internet.wireless (More info?)

"> > > http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
> > > extension cable. I paid $31 for it. So connecting in a cantenna was
> > > simply a matter of drilling a hole then using pliers to enlarge it
> > > enough for the USB connector to go through it. I used a 1-lb coffee
> >
> > Tell me more. I have a DWL-122. I have a coffee can.
> > Did you drill in the bottom, or the side of the can? Where exactly?
How
> > did you decide where to put the mini-USB? How is it oriented inside the
> > can? Have you tried different positioning and orientation within the
can?
> >
> > Can you put up a photo?
> >
> > ---
> > Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>
> A little more info can be found on this posting on my web site:
>
>
http://members.cox.net/tulsaalstons/Documents/Compact%2...
>
> The hole is in the side of the can, at a precise distance from the can
> bottom. The flat part of the DWL-122 faces the open end of the can.
>
> Have not tried different positioning as I found the initial one
> provided excellent results.
>
> Sorry no pictures available right now.
>
> Bob
> Bob

Recently got my USB extension cable for my "tin cantenna". I added a 10
foot cable to the existing 5 foot cable. This is the max for usb. Using
the extension, i placed the tin cantenna forward on my deck. This puts it
immediately above some steel rails on the porch and forward of the upright
supports for the porch roof. The result was an improvement of 8-10 dbi in
the signal to noise ratio. This essentially doubled the difference in
signal vs. noise. I expect this will improve the reliability of my
connection, that had previously occasionally momentarily disconnected or
reduced the transmission rate which is normally at 11 Mbps.

Bob Alston


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Anonymous
July 30, 2004 2:36:29 AM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:
> http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
> http://members.cox.net/tulsaalstons/Documents/Compact%2...

http://makeashorterlink.com/?Q105513C8 goes to the same place.

> supports for the porch roof. The result was an improvement of 8-10 dbi in
> the signal to noise ratio. This essentially doubled the difference in

DLink DWL-122 mini-usb.
I have been playing with various cans. I found that the bare mini-USB is
not omnidirectional at all. It is very sensitive to azimuth, elevation,
and pitch.

My best results appear to be in a two-can setup, using 4" diameter coffee
cans, which seem to be labelled anywhere from 11 oz to 16 oz, depending on
brand, but all the same size. I have one Yuban, and one gourmet brand, the
name of which escapes me. You indicated that a two-can wasn't as good for
you, but I wonder if it isn't just a lot more directional, and difficult to aim.

The difference between vertical and horizontal positioning of the mini-usb
is also important. Try rotating your can 90 degrees. A single large
coffee can seemed to be far more sensitive to the rotation than the other
cans, but ultimately it isn't as good as the two-small-can.

My most recent round of testing still suffers from lack of distance. I
need farther range to see the difference between antennas. NetStumbler
stops being definitive at some saturation point.

The big coffee can is the wrong size according to the calculations, with
too low of a cutoff frequency, but using the mini-usb the radiating
antenna might be better centered in the waveguide. I drilled a small hole,
so that only the USB connector fits through, and the cable connects on the
outside, effectively pinching the can between device and cable.

Is your DWL fully inside the can, or did you drill a much larger hole and
put a portion of the DWL through into the can?

I have a gob of pictures and NetStumbler numbers. I just need to finish.

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
July 30, 2004 2:36:30 AM

Archived from groups: alt.internet.wireless (More info?)

<dold@UsingXUSBX.usenet.us.com> wrote in message
news:cebu5d$72o$1@blue.rahul.net...
> Bob Alston <bobalston AT aol DOT com> wrote:
> > http://www.d-link.com/products/?pid=175 It comes with a 5-foot USB
> >
http://members.cox.net/tulsaalstons/Documents/Compact%2...
>
> http://makeashorterlink.com/?Q105513C8 goes to the same place.
>
> > supports for the porch roof. The result was an improvement of 8-10 dbi
in
> > the signal to noise ratio. This essentially doubled the difference in
>
> DLink DWL-122 mini-usb.
> I have been playing with various cans. I found that the bare mini-USB is
> not omnidirectional at all. It is very sensitive to azimuth, elevation,
> and pitch.
>
> My best results appear to be in a two-can setup, using 4" diameter coffee
> cans, which seem to be labelled anywhere from 11 oz to 16 oz, depending on
> brand, but all the same size. I have one Yuban, and one gourmet brand,
the
> name of which escapes me. You indicated that a two-can wasn't as good for
> you, but I wonder if it isn't just a lot more directional, and difficult
to aim.
>
> The difference between vertical and horizontal positioning of the mini-usb
> is also important. Try rotating your can 90 degrees. A single large
> coffee can seemed to be far more sensitive to the rotation than the other
> cans, but ultimately it isn't as good as the two-small-can.
>
> My most recent round of testing still suffers from lack of distance. I
> need farther range to see the difference between antennas. NetStumbler
> stops being definitive at some saturation point.
>
> The big coffee can is the wrong size according to the calculations, with
> too low of a cutoff frequency, but using the mini-usb the radiating
> antenna might be better centered in the waveguide. I drilled a small
hole,
> so that only the USB connector fits through, and the cable connects on the
> outside, effectively pinching the can between device and cable.
>
> Is your DWL fully inside the can, or did you drill a much larger hole and
> put a portion of the DWL through into the can?
>
> I have a gob of pictures and NetStumbler numbers. I just need to finish.
>
> --
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>

My coffee can was an 11 oz can as I recall and also just about 3.8 inches in
diameter. Slightly larger than ideal but seems to work well for me.

I drilled two holes in the can bottom and inserted the connector part of the
USB stick through the bottom. The connector therefore connects outside the
can.

Since the stick is vertical and the main AP antenna is vertical also, I
think the orientation is correct.

The can made a big difference in reducing noise and other area signals.

Bob Alston


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Anonymous
August 2, 2004 1:09:30 AM

Archived from groups: alt.internet.wireless (More info?)

I just ordered two xterasys usb dongles from mrtechus. Here's my plan I'm
thinking of using the a cantenna with a "horn" of sorts
with the horn being a large coffee can soldered/JB Welded to a smaller 3-3
3/4" can. I saw this idea on another website with
good results on gain and a much wider signal (not so directional) The
dongles that I ordered have a "flip-up"
antenna. I am going to try just cutting a slit in the can and poking the
flip up antenna through the slit at the correct position. Then duct
tape the body of dongle to the outside of the can. The other dongle I'm
thinking of mounting on an old dual lnb DirectTV HDTV oval
dish that I've got laying around. I thought of just taping/mounting the
dongle with the antenna open and pointing back at the dish. I have a
workshop about 300 meters behind my house and I want to connect to the AP in
my house. I do a lot of repair work up there but I don't have
a phone line in the shop. I want to be able to mount the antenna to the
wall in the shop and plug in the USB to any CPU, load the drivers and
be able to access the internet, no fooling around with pci adapters etc. I
have a thumbdrive with the usb drivers on it. I hope it works, I'll let
you know.



Dennis
"Bob Alston" <bobalston AT aol DOT com> wrote in message
news:41097236_3@newsfeed.slurp.net...
> "> > > http://www.d-link.com/products/?pid=175 It comes with a 5-foot
USB
> > > > extension cable. I paid $31 for it. So connecting in a cantenna
was
> > > > simply a matter of drilling a hole then using pliers to enlarge it
> > > > enough for the USB connector to go through it. I used a 1-lb coffee
> > >
> > > Tell me more. I have a DWL-122. I have a coffee can.
> > > Did you drill in the bottom, or the side of the can? Where exactly?
> How
> > > did you decide where to put the mini-USB? How is it oriented inside
the
> > > can? Have you tried different positioning and orientation within the
> can?
> > >
> > > Can you put up a photo?
> > >
> > > ---
> > > Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
> >
> > A little more info can be found on this posting on my web site:
> >
> >
>
http://members.cox.net/tulsaalstons/Documents/Compact%2...
> >
> > The hole is in the side of the can, at a precise distance from the can
> > bottom. The flat part of the DWL-122 faces the open end of the can.
> >
> > Have not tried different positioning as I found the initial one
> > provided excellent results.
> >
> > Sorry no pictures available right now.
> >
> > Bob
> > Bob
>
> Recently got my USB extension cable for my "tin cantenna". I added a 10
> foot cable to the existing 5 foot cable. This is the max for usb. Using
> the extension, i placed the tin cantenna forward on my deck. This puts it
> immediately above some steel rails on the porch and forward of the upright
> supports for the porch roof. The result was an improvement of 8-10 dbi in
> the signal to noise ratio. This essentially doubled the difference in
> signal vs. noise. I expect this will improve the reliability of my
> connection, that had previously occasionally momentarily disconnected or
> reduced the transmission rate which is normally at 11 Mbps.
>
> Bob Alston
>
>
> ---
> Outgoing mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.729 / Virus Database: 484 - Release Date: 7/27/2004
>
>
Anonymous
August 3, 2004 5:34:26 AM

Archived from groups: alt.internet.wireless (More info?)

New info. big rain storm today. Biggest since I installed the extension
cord and moved the cantenna to the edge of my porch.

A key need is to waterproof the connectors. Think I will wrap plastic with
duct tape around the connector for the extension. At the cantenna, I think
I may place the whole thing in a bread wrapper or kitchen plastic bag. Or
maybe just a bag over the adapter stick - - IF I can thread it through the
hole and past the connection to the cable.

--
Bob Alston
http://members.cox.net/tulsaalstons/
"Bob Alston" <bobalston AT aol DOT com> wrote in message
news:41097236_3@newsfeed.slurp.net...
> "> > > http://www.d-link.com/products/?pid=175 It comes with a 5-foot
USB
> > > > extension cable. I paid $31 for it. So connecting in a cantenna
was
> > > > simply a matter of drilling a hole then using pliers to enlarge it
> > > > enough for the USB connector to go through it. I used a 1-lb coffee
> > >
> > > Tell me more. I have a DWL-122. I have a coffee can.
> > > Did you drill in the bottom, or the side of the can? Where exactly?
> How
> > > did you decide where to put the mini-USB? How is it oriented inside
the
> > > can? Have you tried different positioning and orientation within the
> can?
> > >
> > > Can you put up a photo?
> > >
> > > ---
> > > Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
> >
> > A little more info can be found on this posting on my web site:
> >
> >
>
http://members.cox.net/tulsaalstons/Documents/Compact%2...
> >
> > The hole is in the side of the can, at a precise distance from the can
> > bottom. The flat part of the DWL-122 faces the open end of the can.
> >
> > Have not tried different positioning as I found the initial one
> > provided excellent results.
> >
> > Sorry no pictures available right now.
> >
> > Bob
> > Bob
>
> Recently got my USB extension cable for my "tin cantenna". I added a 10
> foot cable to the existing 5 foot cable. This is the max for usb. Using
> the extension, i placed the tin cantenna forward on my deck. This puts it
> immediately above some steel rails on the porch and forward of the upright
> supports for the porch roof. The result was an improvement of 8-10 dbi in
> the signal to noise ratio. This essentially doubled the difference in
> signal vs. noise. I expect this will improve the reliability of my
> connection, that had previously occasionally momentarily disconnected or
> reduced the transmission rate which is normally at 11 Mbps.
>
> Bob Alston
>
>
> ---
> Outgoing mail is certified Virus Free.
> Checked by AVG anti-virus system (http://www.grisoft.com).
> Version: 6.0.729 / Virus Database: 484 - Release Date: 7/27/2004
>
>


---
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Anonymous
August 24, 2004 5:01:44 AM

Archived from groups: alt.internet.wireless (More info?)

Bob Alston <bobalston AT aol DOT com> wrote:
> I drilled two holes in the can bottom and inserted the connector part of the
> USB stick through the bottom. The connector therefore connects outside the
> can.

I had used the calculations on
http://www.turnpoint.net/wireless/cantennahowto.html to determine that the
bare reflector for a cantenna of 4" should be at 1.72" from the bottom of
the can. That's where I put my DWL-122.

Someone else suggested using a slot to determine the optimum location. I
did that today. I cut a 1/2" wide slot in the side of the coffee can, and
mounted the USB gadget though a slice of another coffee can, using rubber
bands to hold it against the side of the coffee cans.
I moved it in roughly 1/4" increments from flush at the back, out to 3".
I found that the best signal was at 2-1/2". Why? The mini-USB is not a
simple radiator. I also found that the cantenna was less directional at
the deeper position. The signal is stable with variation in pointing.

Eventually, I will post some pictures.
For now, you can suffer with this one:
http://www.rahul.net/dold/clarence/usb-can/im000742-800...

--
---
Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
Anonymous
August 24, 2004 5:01:45 AM

Archived from groups: alt.internet.wireless (More info?)

<dold@UsingXUSBX.usenet.us.com> wrote in message
news:cge41o$cb7$1@blue.rahul.net...
> Bob Alston <bobalston AT aol DOT com> wrote:
> > I drilled two holes in the can bottom and inserted the connector part of
the
> > USB stick through the bottom. The connector therefore connects outside
the
> > can.
>
> I had used the calculations on
> http://www.turnpoint.net/wireless/cantennahowto.html to determine that the
> bare reflector for a cantenna of 4" should be at 1.72" from the bottom of
> the can. That's where I put my DWL-122.
>
> Someone else suggested using a slot to determine the optimum location. I
> did that today. I cut a 1/2" wide slot in the side of the coffee can, and
> mounted the USB gadget though a slice of another coffee can, using rubber
> bands to hold it against the side of the coffee cans.
> I moved it in roughly 1/4" increments from flush at the back, out to 3".
> I found that the best signal was at 2-1/2". Why? The mini-USB is not a
> simple radiator. I also found that the cantenna was less directional at
> the deeper position. The signal is stable with variation in pointing.
>
> Eventually, I will post some pictures.
> For now, you can suffer with this one:
> http://www.rahul.net/dold/clarence/usb-can/im000742-800...
>
> --
> ---
> Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8-122.5
>

That is really interesting that the best signal was NOT at the calculated
distance from the back/"can bottom". Something I certainly had not yet
tried.

I saw at Wally World a USB G stick adapter but it does not come with any
cable.

Also I have heard that DWL-122 can be had for about $10 net of rebates if
you watch carefully. Found another brand similarly priced.

--
Bob Alston

bobalston9 AT aol DOT com


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